BIOL 430N Data Visualization

https://tinyurl.com/3423w9xe

February, 2025

What is (are) Research Data?

[R]esearch data represent any material derived from a source of potential information, both measurable and abstract, gathered for analysis or as part of developing findings or insights on a subject.

- Unpublished RDM manuscript.

What are Possible Sources of Data?

people, films, photographs, recordings, artifacts, specimens, music score sheets, art, an existing data set…

How are data classed?

Scales

Nominal (No Order)

Ordinal (Rank Odering)

Interval (Arbitrary Zero, Quantifiable Difference)

Ratio (Proportional)

Stevens, S. (1946). On the theory of scales of Measurement. Science. 103 (2684).

Collection

Counted (Discrete, Observerd)

Measured (Continuous)

Set (Parameter, Categorical)

Reported (Survey, Nominal, Ordinal, Free Text)

Computational Representations

Numeric (integers, rationals)

Character (strings)

Boolean (true, false)…

Attributes

Dates, Currencies, Coordinates…

What is Data Visualization?

The abstraction of data, using shapes, colour, and position.

Source: https://static01.nyt.com/images/2020/11/20/learning/2020electoralvotesmapLN/2020electoralvotesmapLN-superJumbo.png?quality=75&auto=webp

Why do we Visualize Data?

Data visualization is the graphical display of abstract information for two purposes: sense-making (also called data analysis) and communication.

Stephen Few. Data Visualization for Human Perception.

The greatest value of a picture is when it forces us to notice what we never expected to see.

John W. Tukey (1977). “Exploratory Data Analysis”

[T]he […] optic nerves are sending what we now know are 20 megabits a second of information back to the brain […] [It] is being transformed into information, into thinking, right as that step from the retina to the brain. And the brain is really busy, and it likes to economize. And so it’s quick to be active and jump to conclusions. So if you’re told what to look for, you can’t see anything else.

Edward Tufte. Edward Tufte Wants You to See Better. January 18, 2013. Talk of the Nation. https://www.npr.org/2013/01/18/169708761/edward-tufte-wants-you-to-see-better

There is no data that can be displayed in a pie chart, that cannot be displayed better in some other type of chart.

- John W. Tukey. Attributed quote.

There is no such thing as information overload, just bad design. If something is cluttered and/or confusing, fix your design.

- Edward Tufte. Attributed quote.

When does a car stop being safe? https://youtu.be/OnWpZKhDgAo?si=Q1BeQzBFSh_YDted

A beautiful visualization has a clear goal, a message, or a particular perspective on the information that it is designed to convey. Access to this information should be as straightforward as possible, without sacrificing any necessary, relevant complexity.

Noah Iliinsky (2010). On Beauty. In Beautiful visualization: looking at data through the eyes of experts.

The London Tube Map

[Harry] Beck’s … brought [circuit layout] conventions to the Tube map. That freed the map of any attachment to accurate representation of geography and led to an abstracted visual … once you’re in the system, what matters most is your logical relationship to the rest of the subway system. Other maps that accurately show the geography can help you figure out what to do on the surface, but while you’re underground the only surface features that are accessible are the subway stations.

Noah Iliinsky (2010). On Beauty. In Beautiful visualization: looking at data through the eyes of experts.

Source: The Atlantic. (September 17, 2015). Behold, the Geographically Accurate Tube Map. https://www.theatlantic.com/entertainment/archive/2015/09/behold-the-geographically-accurate-tube-map/405967/

Source: London Transport Museum. (n.d.). Artwork; presentation drawing for diagrammatic Underground map, by Henry C Beck, 1931. https://www.ltmuseum.co.uk/collections/collections-online/artwork/item/1993-100

Source: BBC. (n.d.). https://www.bbc.co.uk/london/travel/downloads/tube_map.html

Roberts, M. (August 6, 2024). Round in Circles and Back Again: Updating my London Underground Concentric Circles and Spokes Map. https://www.linkedin.com/pulse/round-circles-back-again-updating-my-london-spokes-map-roberts-dbfpe

“It may well be the best statistical graphic ever drawn.”

Tufte, E. (1983). The Visual Display of Quantitative Information.

Figurative Map of the successive losses in men of the French Army in the Russian campaign 1812–1813. Drawn up by M. Minard, Inspector General of Bridges and Roads in retirement. Paris, 20 November 1869.

Source: https://en.wikipedia.org/wiki/File:Minard.png

Colour, Your Data, Your Audience

Zewe, A. (June 2, 2022). Making data visualization more accessible for blind and low-vision individuals. MIT News. https://news.mit.edu/2022/data-visualization-accessible-blind-0602

Medium (print, digital, distance)

Creating a Colour Scheme

Hue Colour
Saturation Amount of Grey
Luminosity Amount of White and Black

Try building palettes by adjusting a single element at a time.

ColorBrewer Qualitative colour schemes
Data Color Picker Input a colour, request a palette
Picular Word associated colour selections
Color Palette Generator Derive a palette from an image
Colour Maps Generator & Overview
Contrast Checker Evaluate Contrast Ratio
Coblis Colour Blindness Checker